/* global React */
// Jullia — locale plumbing. English is the source of truth (window.JULLIA_I18N.en);
// `t(path)` reads a dotted path from the active locale, falling back to English if
// a key is missing. `localize(item)` overlays a data record's translated fields
// (from its own `i18n[locale]` block) onto the English base — arrays that carry
// non-text data alongside copy (like a gallery's image path) are merged by index
// so translations only need to supply the words.

const LocaleContext = React.createContext(null);

function LocaleProvider({ children }) {
  const [locale, setLocaleState] = React.useState(() => {
    try {
      const saved = localStorage.getItem('jullia_locale');
      if (saved && window.JULLIA_LOCALES && window.JULLIA_LOCALES.includes(saved)) return saved;
    } catch (e) { /* no-op — storage may be unavailable */ }
    return 'en';
  });

  const setLocale = (next) => {
    setLocaleState(next);
    try { localStorage.setItem('jullia_locale', next); } catch (e) { /* no-op */ }
  };

  const dict = (window.JULLIA_I18N && window.JULLIA_I18N[locale]) || {};
  const fallback = (window.JULLIA_I18N && window.JULLIA_I18N.en) || {};

  const t = (path) => {
    const get = (obj) => path.split('.').reduce((o, k) => (o && o[k] !== undefined ? o[k] : undefined), obj);
    const v = get(dict);
    return v !== undefined ? v : get(fallback);
  };

  const localize = (item) => {
    if (!item) return item;
    const overrides = item.i18n && item.i18n[locale];
    if (!overrides) return item;
    const merged = { ...item, ...overrides };
    if (overrides.gallery && item.gallery) {
      merged.gallery = item.gallery.map((g, i) => ({ ...g, ...(overrides.gallery[i] || {}) }));
    }
    return merged;
  };

  const value = { locale, setLocale, t, localize };
  return <LocaleContext.Provider value={value}>{children}</LocaleContext.Provider>;
}

function useLocale() {
  return React.useContext(LocaleContext);
}

Object.assign(window, { LocaleProvider, useLocale });